Optimizing the concentration of hydroxyethylstarch in a novel intestinal-specific preservation solution

Introduction: Our lab has developed an effective nutrient-rich solution that facilitates energy production and control of oxidative stress during static cold storage of the intestine; however, the requirement for oncotic agents, such as hydroxyethylstarch (HES), has not been evaluated. This study investigated the effectiveness and requirement for HES in an intraluminal preservation solution during a clinically relevant period of cold storage. Methods: Rat intestines were procured, including an intravascular flush with University of Wisconsin solution followed by a 'back table' intraluminal flush with a nutrient-rich preservation solution containing varying amounts of HES ( n= 6 per group): Group 1, 0%; Group 2, 2.5%; Group 3, 5%; Group 4, 10%. Energetics, oxidative stress, and morphology were assessed over a 24. h time-course of cold storage. Results: Overall, the 5% HES solution, Group 3, demonstrated superior energetic status (ATP and total adenylates) compared to all groups,. P< 0.05. Malondialdehyde levels indicated a reduction in oxidative stress in Groups 3 and 4 ( P< 0.05). After 12. h, median modified Parks' grades for Groups 2 and 3 were significantly lower than Groups 1 and 4,. P< 0.05. Conclusion: Our data suggests that when employing an intraluminal preservation solution for static organ storage, oncotic support is a fundamental requirement; 5% HES is optimal.